UCLA High Energy Density Plasma Physics

Post-doc Robert Dorst and Project Scientist Carmen Constantin on top of the Large Plasma Device during a laser-shock experiment.

Professor Christoph Niemann

The High Energy Density Plasma (HEDP) group works in the area of experimental laser-plasma physics, with an emphasis on laboratory astrophysics and the development of laser-based plasma diagnostics. The group operates the PHOENIX laser laboratory, which includes one of the highest-energy lasers at a university and one of the few fully operational high-energy, high-repetition-rate laser-plasma experiments.

Last year, graduate student Jessica Pilgram and undergraduate student Haiping Zhang developed a new raster Thomson scattering system and used it to make the first accurate two-dimensional measurements of the misaligned density and temperature gradients responsible for spontaneous magnetic field generation in plasmas via the so-called “Biermann battery” effect. Postdocs Robert Dorst and Lucas Rovige used a novel laser-induced fluorescence system to map out the ion phase space in exploding laser plasmas in the 20 meter long Large Plasma Device. These measurements show how energy is coupled between the laser plasma and the ambient plasma, helping to better understand explosions in space and astrophysical plasmas.  Doing properly scaled physics experiments in a controlled laboratory setting can help shed some light on the origin of cosmic rays and magnetic fields throughout the cosmos.

The PHOENIX laser laboratory recently joined LaserNetUS, a consortium of some of the nation’s largest laser facilities established by the DOE to provide students and researchers with broad access to unique experimental capabilities. As a new LaserNetUS node, UCLA will support scaled experiments to help develop laser-fusion as a potential carbon-free and unlimited energy source for the future. The much larger National Ignition Facility (NIF) at Lawrence Livermore National Laboratory has recently demonstrated the concept for the first time. While a laser the size of NIF is required to ignite a target, the PHOENIX laser will support experiments that investigate the laser-target and chamber coupling and test the required scientific instruments.

First two-dimensional Thomson scattering measurement of misaligned plasma density and temperature gradients.